Organometallic compound and organic light-emitting device including the same

ABSTRACT

An organometallic compound and an organic light-emitting device, the organometallic compound being represented by the following Formula 1:
 
M(L 1 ) n1 (L 2 ) n2   &lt;Formula 1&gt;
         wherein in Formula 1, M is selected from iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), and rhodium (Rh); n1 is 0, 1, 2, or 4; n2 is 1, 2, or 3; when n1 is two or more, two or more L 1  are identical or different, and when n2 is two or more, two or more L 2  are identical to different; L 1  is selected from a monovalent organic ligand, a divalent organic ligand, a trivalent organic ligand, and a tetravalent organic ligand, and is different from L 2 ; L 2  is a ligand represented by the following Formula 2;

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2014-0194319, filed on Dec. 30, 2014,in the Korean Intellectual Property Office, and entitled:“Organometallic Compound and Organic Light-Emitting Device Including TheSame,” is incorporated by reference herein in its entirety.

BACKGROUND

1. Field

Embodiments relate to an organometallic compound and an organiclight-emitting device including the same.

2. Description of the Related Art

Organic light emitting devices are self-emission devices that have wideviewing angles, high contrast ratios, short response times, andexcellent brightness, driving voltage, and response speedcharacteristics, and produce full-color images.

The organic light-emitting device may include a first electrode disposedon a substrate, and a hole transport region, an emission layer, anelectron transport region, and a second electrode, which aresequentially disposed on the first electrode. Holes provided from thefirst electrode may move toward the emission layer through the holetransport region, and electrons provided from the second electrode maymove toward the emission layer through the electron transport region.Carriers, such as holes and electrons, are recombined in the emissionlayer to produce excitons. These excitons change from an excited stateto a ground state, thereby generating light.

SUMMARY

Embodiments are directed to an organometallic compound and an organiclight-emitting device including the same.

An aspect provides an organometallic compound represented by Formula 1below:M(L₁)_(n1)(L₂)_(n2)  <Formula 1>

wherein in Formula 1,

M is selected from iridium (Ir), platinum (Pt), osmium (Os), titanium(Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium(Tm), and rhodium (Rh);

L₁ is selected from a monovalent organic ligand, a divalent organicligand, a trivalent organic ligand, and a tetravalent organic ligand,and is different from L₂;

L₂ is selected from a ligand represented by Formula 2;

n1 is 0, 1, 2, or 4;

n2 is 1, 2, or 3;

when n1 is two or more, two or more L₁ are identical or different, andwhen n2 is two or more, two or more L₂ are identical to different:

wherein in Formula 2,

X₁ is N (nitrogen) or C(R₁), X₂ is N or C(R₂), X₃ is N or C(R₃), and X₄is N or C(R₄);

X₅ is N, C (carbon), or C(R₅), X₆ is N, C, or C(R₆), X₇ is N, C, orC(R₇), X₈ is N, C, or C(R₈), two selected from X₅ to X₈ are C,

when X₅ is C, X₅ binds to M or N of a benzimidazole-based ring inFormula 1; when X₆ is C, X₆ binds to M or N of the benzimidazole-basedring in Formula 1; when X₇ is C, X₇ binds to M or N of abenzimidazole-based ring in Formula 1; when X₈ is C, X₈ binds to M or Nof a benzimidazole-based ring in Formula 1;

X₉ is N or C(R₉), X₁₀ is N or C(R₁₀), X₁₁ is N or C(R₁₁), X₁₂ is N orC(R₁₂);

R₁ to R₁₄ may be each independently selected from a hydrogen, adeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —C(═O)(Q₈);

two selected from R₁ to R₄ may optionally bind to each other to form asaturated or unsaturated ring, two selected from R₉ to R₁₂ mayoptionally bind to each other to form a saturated or unsaturated ring.R₁₃ and R₁₄ may optionally bind to each other to form a saturated orunsaturated ring:

* and *′ each indicate a binding site to M in Formula 1;

at least one substituent of the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arythio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅),—B(Q₁₆)(Q₁₇), and —C(═O)(Q₁₈);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic heterocondensed polycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅),—B(Q₂₆)(Q₂₇), and —C(═O)(Q₂₈); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇), and —C(═O)(Q₃₈);

wherein Q₁ to Q₈, Q₁₁ to Q₁₈, Q₂₁ to Q₂₈, and Q₃₁ to Q₃₈ may be eachindependently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arythio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group.

Another aspect provides an organic light-emitting device including: afirst electrode; a second electrode facing the first electrode; and anorganic layer that is disposed between the first electrode and thesecond electrode and includes an emission layer, wherein the organiclayer includes at least one organometallic compound represented byFormula 1.

BRIEF DESCRIPTION OF THE DRAWING

Features will be apparent to those of skill in the art by describing indetail exemplary embodiments with reference to the attached drawing inwhich:

FIG. 1 illustrates a schematic view of an organic light-emitting deviceaccording to an embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawing; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art.

In the drawing FIGURE, the dimensions of layers and regions may beexaggerated for clarity of illustration. Like reference numerals referto like elements throughout.

An organometallic compound according to an embodiment may be representedby Formula 1 below.M(L₁)_(n1)(L₂)_(n2)  <Formula 1>

In Formula 1, M may be selected from, e.g., iridium (Ir), platinum (Pt),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), thulium (Tm), and rhodium (Rh).

In Formula 1, L₁ may be selected from, e.g., a monovalent organicligand, a divalent organic ligand, a trivalent organic ligand, and atetravalent organic ligand. L₂ may be, e.g., a ligand represented by thefollowing Formula 2. L₁ may be different from L₂.

In Formula 1, n1 may be 0, 1, 2, or 4, and n2 may be 1, 2, or 3.

In an implementation, when M is iridium (Ir), n1 may be 0, 1 or 2, n2may be 1, 2 or 3, and a sum of n1 and n2 may be 3. In an implementation,when M is platinum (Pt), n1 may be 0, 1, or 2, n2 may be 1 or 2, and thesum of n1 and n2 may be 2.

n1 in Formula 1 indicates the number of L₁, and may be 0, 1, 2, or 4.When n1 is 2 or more, 2 or more L₁ may be identical or different.

n2 in Formula 1 indicates the number of L₂, and may be 1, 2, or 3. Whenn2 is 2 or more, 2 or more L₂ may be identical or different.

In Formula 2, X₁ may be N (nitrogen) or C(R₁), X₂ may be N or C(R₂), X₃may be N or C(R₃), and X₄ may be N or C(R₄). R₁ to R₄ are describedbelow.

In an implementation, X₁ may be C(R₁), X₂ may be C(R₂), X₃ may be C(R₃),and X₄ may be C(R₄).

In Formula 2, X₅ may be N, C (carbon), or C(R₅), X₆ may be N, C, orC(R₆), may be N, C, or C(R₇), X₈ may be N, C, or C(R₈), and two selectedfrom X₅ to X₈ may be C. R₅ to R₈ are described below.

In an implementation, when X₅ is C, X₅ may bind to M or N of thebenzimidazole-based moiety in Formula 1 (e.g., of Formula 2); when X₆ isC, X₆ may bind to M or N of the benzimidazole-based moiety in Formula 2;when X₇ is C, X₇ may bind to M or N of the benzimidazole-based moiety inFormula 2; or when X₈ is C, X₈ may bind to M or N of thebenzimidazole-based moiety in Formula 2.

In an implementation, X₅ and X₆ may be C; X₆ and X₇ may be C; or X₇ andX₈ may be C.

In Formula 2, X₉ may be N or C(R₉), X₁₀ may be N or C(R₁₀), X₁₁ may be Nor C(R₁₁), and X₁₂ may be N or C(R₁₂). R₉ to R₁₂ are described below.

In an implementation, X₉ may be C(R₉), X₁₀ may be C(R₁₀), X₁₁ may beC(R₁₁), and/or X₁₂ may be C(R₁₂).

R₁ to R₁₄ may each independently be selected from or include, e.g., ahydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic heterocondensedpolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and—C(═O)(Q₈). Q₁ to Q₈ are described below.

In an implementation, R₁ to R₁₂ in Formula 2 may each independently beselected from:

a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, or an imidazopyrimidinyl group, each substituted with at leastone selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, and —Si(Q₃₃)(Q₃₄)(Q₃₅); and

—Si(Q₃)(Q₄)(Q₅),

wherein Q₃ to Q₅ and Q₃₃ to Q₃₅ may each independently be selected froma hydrogen, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a quinolinyl group, and an isoquinolinyl group.

In an implementation, R₁ to R₁₂ in Formula 2 may each independently beselected from:

a hydrogen, —F, a cyano group, a nitro group, a methyl group, an ethylgroup, a propyl group, an n-butyl group, an isobutyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an isopentyl group, asec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decanyl group, an isodecanyl group, a sec-decanyl group, atert-decanyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, or a triazinyl group;

a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, or a triazinylgroup, each substituted with at least one selected from —F, a cyanogroup, a nitro group, a phenyl group, a naphthyl group, a pyridinylgroup, a pyrimidinyl group, a triazinyl group, and —Si(Q₃₃)(Q₃₄)(Q₃₅);and

—Si(Q₃)(Q₄)(Q₅),

wherein Q₃ to Q₅ and Q₃₃ to Q₃₅ may each independently be selected froma hydrogen, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a quinolinyl group, and an isoquinolinyl group.

In an implementation, R₁ to R₄ may be separate or two of R₁ to R₄ maybind to each other to form a saturated or unsaturated ring and/or R₉ toR₁₂ may be separate or two of R₉ to R₁₂ may bind to each other to form asaturated or unsaturated ring.

In an implementation, R₁₃ and R₁₄ in Formula 2 may each independently beselected from:

a hydrogen, —F, a cyano group, a nitro group, a methyl group, an ethylgroup, a propyl group, an n-butyl group, an isobutyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an isopentyl group, asec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decanyl group, an isodecanyl group, a sec-decanyl group, atert-decanyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, and a pentoxy group;

a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, and a pentoxy group, eachsubstituted with at least one selected from —F, a cyano group, a nitrogroup, a phenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, or an imidazopyrimidinyl group, each substituted with at leastone selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, and —Si(Q₃₃)(Q₃₄)(Q₃₅); and

—Si(Q₃)(Q₄)(Q₅),

wherein Q₃ to Q₅ and Q₃₃ to Q₃₅ may be each independently selected froma hydrogen, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a quinolinyl group, and an isoquinolinyl group.

In an implementation, R₁₃ and R₁₄ in Formula 2 may each independently beselected from:

a hydrogen, —F, a cyano group, a nitro group, a methyl group, an ethylgroup, a propyl group, an n-butyl group, an isobutyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an isopentyl group, asec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decanyl group, an isodecanyl group, a sec-decanyl group, atert-decanyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, and a pentoxy group;

a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, and a pentoxy group, eachsubstituted with at least one selected from —F, a cyano group, a nitrogroup, a phenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a triphenylenylgroup, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, apyridazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinylgroup; and

a phenyl group, a naphthyl group, an anthracenyl group, a triphenylenylgroup, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, apyridazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinylgroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a naphthyl group, an anthracenyl group, atriphenylenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinylgroup.

In an implementation, R₁₃ and R₁₄ in Formula 2 may each independently bea hydrogen or a phenyl group.

In an implementation, R₁₃ and R₁₄ may be separate or R₁₃ and R₁₄ maybind to each other to form a saturated or unsaturated ring.

* and *′ in Formula 2 are binding sites to M in Formula 1.

In an implementation, L₂ in Formula 1 may be a ligand represented by oneof the following Formulae 2A to 2F.

R₁ to R₁₄, *, and *′ in Formulae 2A to 2F may be the same as definedabove with respect to Formula 2.

In an implementation, L₁ in Formula 1 may be a ligand represented by thefollowing Formula 3.

Y₁ to Y₄ in Formula 3 may each independently be carbon (C) or nitrogen(N).

In an implementation, in Formula 3, Y₁ may be C and Y₄ may be N.

In an implementation, in Formula 3, Y₂ and Y₃ may be C.

Y₁ and Y₂ in Formula 3 may be linked to each other via a single bond ora double bond, and Y₃ and Y₄ may be linked to each other via a singlebond or a double bond.

CY₁ and CY₂ in Formula 3 may each independently be or form a C₅-C₆₀cyclic group or a C₁-C₆₀ heterocyclic group. For example, CY₁ includesY₁ and Y₂ to form a C₅-C₆₀ cyclic group or a C₁-C₆₀ heterocyclic group,and CY₂ includes Y₃ and Y₄ to form a C₅-C₆₀ cyclic group or a C₁-C₆₀heterocyclic group.

R₂₁ and R₂₂ in Formula 3 may each independently be selected from orinclude, e.g., a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic heterocondensedpolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and B(Q₆)(Q₇). Q₁ to Q₇are described below.

In an implementation, CY₁ and CY₂ may each independently be selectedfrom or form (e.g., with Y₁ to Y₄) benzene group, a naphthalene group, afluorene group, a spiro-fluorene group, an indene group, a pyrrol group,a thiophene group, a furan group, a imidazole group, a pyrazole group, athiazole group, an isothiazole group, an oxazole group, an isoxazolegroup, a pyridine group, a pyrazine group, a pyrimidine group, apyridazine group, a quinoline group, an isoquinoline group, abenzoquinoline group, a quinoxaline group, a quinazoline group, acarbazole group, a benzoimidazole group, a benzofuran group, abenzothiophene group, an isobenzothiophene group, a benzoxazole group,an isobenzoxazole group, a triazole group, a tetrazole group, anoxadiazole group, a triazine group, a dibenzofuran group, and/or adibenzothiophene group.

In an implementation, R₂₁ and R₂₂ may each independently be selectedfrom:

a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,—SF₅, a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, an imidazopyrimidinyl group, and —Si(Q₄₁)(Q₄₂)(Q₄₃), eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group,a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthrolinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group;

Q₄₁ to Q₄₃ may be each independently selected from a hydrogen, a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, and a triazinyl group.

In an implementation, CY₁ may be or form, e.g., a benzene group, apyridine group, a pyrimidine group, or a triazine group, and CY₂ may beor form, e.g., a pyridine group, an imidazole group, a pyrazole group, atriazole group, or a tetrazole group.

In an implementation, R₂₁ and R₂₂ may each independently be selectedfrom:

a hydrogen, —F, a cyano group, a nitro group. —SF₅, a methyl group, anethyl group, a propyl group, an n-butyl group, an isobutyl group, asec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, anisohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptylgroup, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, ann-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group,an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonylgroup, an n-decanyl group, an isodecanyl group, a sec-decanyl group, atert-decanyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a triazinyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a dibenzofuranyl group and a dibenzothiophenyl group, eachsubstituted with at least one selected from —F, a cyano group and anitro group.

a1 and a2 in Formula 3 may each independently be an integer selectedfrom 1, 2, 3, 4, and 5. For example, a1 and a2 may each independently be0, 1, 2, or 3.

a1 in Formula 3 indicates the number of R₂₁, and when a1 is 2 or more,two or more R₂₁ may be identical or different.

a2 in Formula 3 indicates the number of R₂₂, and when a2 is 2 or more,two or more R₂₂ may be identical or different.

* and *′ in Formula 3 are binding sites to M in Formula 1.

In an implementation, L₁ in Formula 1 may be a ligand represented by oneof the following Formulae 3-1 to 3-24.

In Formulae 3-1 to 3-24,

R₂₁ and R₂₂ may each independently be selected from:

a hydrogen, —F, a cyano group, a nitro group, —SF₅, a methyl group, anethyl group, a propyl group, an n-butyl group, an isobutyl group, asec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, anisohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptylgroup, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, ann-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group,an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonylgroup, an n-decanyl group, an isodecanyl group, a sec-decanyl group, atert-decanyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a triazinyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a dibenzofuranyl group and a dibenzothiophenyl group, eachsubstituted with at least one selected from —F, a cyano group and anitro group;

a11 and a21 may each independently be 1, 2, 3, or 4; a12 and a22 mayeach independently be 1, 2, or 3, a13 and a23 may each independently be1 or 2;

* and *′ each indicate a binding site to M in Formula 1.

In an implementation, L₁ may be a ligand represented by one of thefollowing Formulae 4-1 to 4-4.

In Formulae 4-1 to 4-4,

Z_(21b), Z_(21c), Z_(21d), and Z_(22b) may each independently beselected from:

—F, a cyano group, a nitro group, a methyl group, an ethyl group, apropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, atert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, an n-hexyl group, an isohexyl group, asec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptylgroup, a sec-heptyl group, a tert-heptyl group, an n-octyl group, anisooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group,an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decanylgroup, an isodecanyl group, a sec-decanyl group, a tert-decanyl group, amethoxy group, an ethoxy group, a propoxy group, a butoxy group, apentoxy group, a phenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group;

a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, and atriazinyl group, each substituted with at least one selected from —F, acyano group, a nitro group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a triazinyl group, and—Si(Q₃₃)(Q₃₄)(Q₃₅); and

—Si(Q₃)(Q₄)(Q₅);

wherein Q₃ to Q₅ and Q₃₃ to Q₃₅ may each independently be selected froma hydrogen, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a quinolinyl group, and an isoquinolinyl group.

For example, Z_(21b), Z_(21c), and Z_(21d) may each independently beselected from —F, —Cl, —CN and —NO₂; and a C₁-C₂₀ alkyl group and aC₁-C₂₀ alkoxy group, each substituted with at least one selected from—F, —Cl, —CN, and —NO₂.

Z_(22b) may be selected from a C₁-C₂₀ alkyl group and —N(Q₄₁)(Q₄₂), and

Q₄₁ and Q₄₂ may each independently be selected from a hydrogen, a C₁-C₂₀alkyl group, a phenyl group, a naphthyl group, and an anthracenyl group.

In an implementation, the organometallic compound represented by Formula1 may be represented by one of the following Formulae 1-1 to 1-24.

In Formulae 1-1 to 1-24,

M may be, e.g., iridium (Ir) or platinum (Pt);

n1 may be 0, 1, or 2, n2 may be 1, 2, or 3, and a sum of n1 and n2 maybe 2 or 3.

R₁ to R₁₂ may each independently be selected from:

a hydrogen, —F, a cyano group, a nitro group, a methyl group, an ethylgroup, a propyl group, an n-butyl group, an isobutyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an isopentyl group, asec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decanyl group, an isodecanyl group, a sec-decanyl group, atert-decanyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, and a triazinyl group;

a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, or a triazinylgroup, each substituted with at least one selected from —F, a cyanogroup, a nitro group, a phenyl group, a naphthyl group, a pyridinylgroup, a pyrimidinyl group, a triazinyl group, and —Si(Q₃₃)(Q₃₄)(Q₃₅);and

—Si(Q₃)(Q₄)(Q₅),

wherein Q₃ to Q₅ and Q₃₃ to Q₃₅ may each independently be selected froma hydrogen, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a quinolinyl group, and an isoquinolinyl group.

R₁₃ and R₁₄ may each independently be selected from a hydrogen or aphenyl group.

R_(21b), R_(21c), and R_(21d) may each independently be selected from—F, —Cl, —CN and —NO₂; and a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxygroup, each substituted with at least one selected from —F, —Cl, —CN,and —NO₂,

R_(22b) may be selected from a C₁-C₂₀ alkyl group and —N(Q₄₁)(Q₄₂), and

Q₄₁ and Q₄₂ may each independently be selected from a hydrogen, a C₁-C₂₀alkyl group, a phenyl group, a naphthyl group, and an anthracenyl group.

In an implementation, the organometallic compound represented by Formula1 may be one of the following Compounds 1 to 5 and 7 to 34.

Regarding the organometallic compound, in a ligand illustrated inFormula 2A′ below, a benzimidazole-based moiety and a carbazole-basedmoiety in which a triazolyl group binds to an N atom, may bind to acentral metal (M). The benzimidazole-based moiety may be an electrondonating group and the carbazole-based moiety may be an electronwithdrawing group. Herein, a carbazole-based moiety in the ligand mayhave lower electron density due to the binding of the trizaolyl grouphaving strong electron withdrawing characteristics to the N atom acarbazole-based moiety. By doing this, in the organometallic compound,electronic stability at a highest occupied molecular orbital (HOMO)level may be increased and electronic unstability at a lowest unoccupiedmolecular orbital (LUMO) level may be increased. Thus, an energy bandgap between a HOMO level and a LUMO level may be increased. As a result,light emitted by the organometallic compound may be light that has beenshifted toward a shorter wavelength, e.g., blue-shift light. The ligandof the organometallic compound may easily traps electrons, so that theelectrons may form many excitons together with holes provided into anemission layer including the organometallic compound. Accordingly, anorganic light-emitting device using the organometallic compound may havehigh luminescent efficiency.

Accordingly, an organic light-emitting device using or including theorganometallic compound represented by Formula 1 may have a low-drivingvoltage and high brightness.

The organometallic compound represented by Formula 1 may be synthesizedby a suitable organic synthetic method. A synthesis method of theorganometallic compound may be understood in view of the followingembodiments.

The organometallic compound of Formula 1 may be used between a pair ofelectrodes of an organic light-emitting device. In an implementation,the organometallic compound may be included in an electron transportregion, e.g., an electron transport layer. In an implementation, theorganometallic compound may be included in an emission layer, e.g., as adopant. For example, an organic light-emitting device according to anembodiment may include: a first electrode; a second electrode facing thefirst electrode; and an organic layer between the first electrode andthe second electrode and that includes an emission layer. The organiclayer may include at least one of the organometallic compounds describedabove.

The expression “(an organic layer) includes at least one organometalliccompounds” used herein may include a case in which “(an organic layer)includes identical organometallic compounds of Formula 1 and a case inwhich (an organic layer) includes two or more different organometalliccompounds of Formula 1.

For example, the organic layer may include, as the organometalliccompound, only Compound 1. In this regard, Compound 1 may exist in anemission layer of the organic light-emitting device. In someembodiments, the organic layer may include, as the organometalliccompound, Compound 1 and Compound 2. In this regard, Compound 1 andCompound 2 may exist in an identical layer (for example, Compound 1 andCompound 2 may all exist in an emission layer), or different layers (forexample, Compound 1 may exist in an emission layer and Compound 2 mayexist in an electron transport layer).

The organic layer may include i) a hole transport region that isdisposed between the first electrode (anode) and the emission layer andincludes at least one of a hole injection layer, a hole transport layer,a buffer layer, and an electron blocking layer, and/or ii) an electrontransport region that is disposed between the emission layer and thesecond electrode (cathode) and includes at least one selected from ahole blocking layer, an electron transport layer, and an electroninjection layer. The emission layer may include the organometalliccompound represented by Formula 1.

The term “organic layer” used herein refers to a single layer and/or aplurality of layers disposed between the first electrode and the secondelectrode of an organic light-emitting device. A material included inthe “organic layer” is not limited to an organic material.

FIG. 1 illustrates a schematic view of an organic light-emitting device10 according to an embodiment. The organic light-emitting device 10includes a first electrode 110, an organic layer 150, and a secondelectrode 190.

Hereinafter, the structure of an organic light-emitting device accordingto an embodiment and a method of manufacturing an organic light-emittingdevice according to an embodiment will be described in connection withFIG. 1.

In FIG. 1, a substrate may be additionally disposed under the firstelectrode 110 or above the second electrode 190. The substrate may be aglass substrate or transparent plastic substrate, each with excellentmechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and water-resistance.

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode on the substrate. When thefirst electrode 10 is an anode, the material for the first electrode maybe selected from materials with a high work function to make holes beeasily injected. The first electrode 110 may be a reflective electrodeor a transmissive electrode. The material for the first electrode may bea transparent and highly conductive material, and examples of such amaterial are indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide(SnO₂), and zinc oxide (ZnO). When the first electrode 110 is asemi-transmissive electrode or a reflective electrode, as a material forforming the first electrode, at least one of magnesium (Mg), aluminum(Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In),magnesium-silver (Mg—Ag) may be used.

The first electrode 110 may have a single-layer structure, or amulti-layer structure including two or more layers. For example, thefirst electrode 110 may have a three-layered structure of ITO/Ag/ITO.

An organic layer 150 may be disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport regiondisposed between the first electrode and the emission layer, and/or anelectron transport region disposed between the emission layer and thesecond electrode.

The hole transport region may include at least one selected from a holeinjection layer (HIL), a hole transport layer (HTL), a buffer layer, andan electron blocking layer (EBL), and the electron transport region mayinclude at least one selected from a hole blocking layer (HBL), anelectron transport layer (ETL), and an electron injection layer (EIL).

The hole transport region may have a single-layered structure formed ofa single material, a single-layered structure formed of a plurality ofdifferent materials, or a multi-layered structure having a plurality oflayers formed of a plurality of different materials.

For example, the hole transport region may have a single-layeredstructure formed of a plurality of different materials, or a structureof hole injection layer/hole transport layer, a structure of holeinjection layer/hole transport layer/buffer layer, a structure of holeinjection layer/buffer layer, a structure of hole transport layer/bufferlayer, or a structure of hole injection layer/hole transportlayer/electron blocking layer, wherein layers of each structure aresequentially stacked from the first electrode 110 in this stated order.

When the hole transport region includes a hole injection layer, the holeinjection layer may be formed on the first electrode 110 by usingvarious methods, such as vacuum deposition, spin coating casting, aLangmuir-Blodgett (LB) method, ink-jet printing, laser-printing, orlaser-induced thermal imaging.

When a hole injection layer is formed by vacuum deposition, for example,the vacuum deposition may be performed at a temperature of a depositiontemperature of about 100 to about 500° C., at a vacuum degree of about10⁻⁸ to about 10⁻³ torr, and at a deposition rate of about 0.01 to about100 Å/sec in consideration of a compound for a hole injection layer tobe deposited, and the structure of a hole injection layer to be formed.

When a hole injection layer is formed by spin coating, the spin coatingmay be performed at a coating rate of about 2000 rpm to about 5000 rpm,and at a temperature of about 80° C. to 200° C. in consideration of acompound for a hole injection layer to be deposited, and the structureof a hole injection layer to be formed.

When the hole transport region includes a hole transport layer, the holetransport layer may be formed on the first electrode 110 or the holeinjection layer by using various methods, such as vacuum deposition,spin coating, casting, a LB method, ink-jet printing, laser-printing, orlaser-induced thermal imaging. When the hole transport layer is formedby vacuum deposition or spin coating, deposition and coating conditionsfor the hole transport layer may be determined by referring to thedeposition and coating conditions for the hole injection layer.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, α-NPB,TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA),polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonicacid (Pani/CSA),(polyaniline)/poly(4-styrenesulfonate) (PANI/PSS), a compoundrepresented by Formula 201 below, and a compound represented by Formula202 below:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group;

xa1 to xa4 may each independently be selected from 0, 1, 2, and 3;

xa5 may be selected from 1, 2, 3, 4, and 5; and

R₂₀₁ to R₂₀₄ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

In some embodiments, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorene group, a dibenzofluorenegroup, a phenanthrenylene group, an anthracenylene group, a pyrenylenegroup, a chrysenylene group, a pyridinylene group, a pyrazinylene group,a pyrimidinylene group, a pyridazinylene group, a quinolinylene group,an isoquinolinylene group, a quinoxalinylene group, a quinazolinylenegroup, a carbazolylene group, and a triazinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorene group, a dibenzofluorenegroup, a phenanthrenylene group, an anthracenylene group, a pyrenylenegroup, a chrysenylene group, a pyridinylene group, a pyrazinylene group,a pyrimidinylene group, a pyridazinylene group, a quinolinylene group,an isoquinolinylene group, a quinoxalinylene group, a quinazolinylenegroup, a carbazolylene group, and a triazinylene group, each substitutedwith at least one selected from a deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, anaphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anisoindolyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group;

xa1 to xa4 may each independently be 0, 1, or 2;

xa5 may be 1, 2, or 3;

R₂₀₁ to R₂₀₄ may each independently be selected from

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, an azulenyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group.

The compound represented by Formula 201 may be represented by Formula201A:

For example, the compound represented by Formula 201 may be representedby Formula 201A-1 below.

For example, the compound represented by Formula 202 may be representedby Formula 202A below.

L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ in Formulae 201A,201A-1, and 202A are already described above, R₂₁₁ is the same asdefined in connection with R₂₀₃, and R₂₁₃ to R₂₁₆ may be eachindependently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid group ora salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid ora salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monvalentnon-aromatic condensed polycyclic group, and a monvalent non-aromaticcondensed heteropolycyclic group.

For example, in Formulae 201A, 201A-1, and 202A,

L₂₀₁ to L₂₀₃ may each independently be selected from

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a naphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group;

xa1 to xa3 may each independently be 0 or 1;

R₂₀₃, R₂₁₁, and R₂₁₂ may each independently be selected from

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group;

R₂₁₃ and R₂₁₄ may each independently be selected from

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group and a triazinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group;

R₂₁₅ and R₂₁₆ may each independently be selected from

a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group and a triazinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group;

xa5 is 1 or 2.

R₂₁₃ and R₂₁₄ in Formulae 201A, and 201A-1 may bind to each other toform a saturated or unsaturated ring.

The compound represented by Formula 201, and/or the compound representedby Formula 202 may include compounds HT1 to HT20 illustrated below.

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, e.g., about 100 Å to about 1000 Å. When the holetransport region includes a hole injection layer and a hole transportlayer, the thickness of the hole injection layer may be in a range ofabout 100 Å to about 10,000 Å, e.g., about 100 Å to about 1,000 Å, andthe thickness of the hole transport layer may be in a range of about 50Å to about 2,000 Å, e.g., about 100 Å to about 1,500 Å. When thethicknesses of the hole transport region, the hole injection layer, andthe hole transport layer are within these ranges, satisfactory holetransporting characteristics may be obtained without a substantialincrease in driving voltage.

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or unhomogeneously dispersed in the hole transport region.

The charge-generation material may be, for example, a p-dopant. Thep-dopant may include one selected from a quinone derivative, a metaloxide, and a cyano group-containing compound. Examples of the p-dopantmay include a quinone derivative, such as tetracyanoquinonedimethane(TCNQ) or 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane(F4-TCNQ); a metal oxide, such as a tungsten oxide or a molybdenumoxide, and Compound HT-D1 illustrated below.

The hole transport region may further include, in addition to the holeinjection layer and the hole transport layer, at least one of a bufferlayer and an electron blocking layer. Since the buffer layer maycompensate for an optical resonance distance according to a wavelengthof light emitted from the emission layer, light-emission efficiency of aformed organic light-emitting device may be improved. For use as amaterial included in the buffer layer, materials that are included inthe hole transport region may be used. The electron blocking layerprevents injection of electrons from the electron transport region.

For example, a material for the electron blocking layer may be mCP.

An emission layer may be formed on the first electrode 110 or the holetransport region by using various methods, e.g., vacuum deposition, spincoating, casting, a LB method, ink-jet printing, laser-printing, orlaser-induced thermal imaging. When the emission layer is formed byvacuum deposition or spin coating, deposition and coating conditions forthe emission layer may be determined by referring to the deposition andcoating conditions for the hole injection layer.

When the organic light-emitting device 10 is a full color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, or a blue emission layer,according to a sub pixel. In some embodiments, the emission layer mayhave a stacked structure of a red emission layer, a green emissionlayer, and a blue emission layer, or may include a red-light emissionmaterial, a green-light emission material, and a blue-light emissionmaterial, which are mixed with each other in a single layer, to emitwhite light.

The emission layer may include the organometallic compound representedby Formula 1.

The emission layer may include a host and a dopant. The dopant mayinclude the organometallic compound represented by Formula 1.

The host may include at least one selected from TPBi, TBADN, ADN (alsoreferred to as “DNA”), CBP, CDBP, and TCP:

In some embodiments, the host may include a compound represented byFormula 301 below.Ar₃₀₁-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb2)  <Formula 301>

wherein in Formula 301,

Ar₃₀₁ may be selected from

naphthalene, heptalene, fluorenene, spiro-fluorenene, benzofluorenene,dibenzofluorenene, phenalene, phenanthrene, anthracene, fluoranthene,triphenylene, pyrene, chrysene, naphthacene, picene, perylene,pentaphene, and indenoanthracene;

a naphthalene group, a heptalene group, a fluorenene group, aspiro-fluorenene group, a benzofluorenene group, a dibenzofluorenenegroup, a phenalene group, a phenanthrene group, a anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, and an indenoanthracene group, each substituted withat least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, and—Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃) (wherein Q₃₀₁ to Q₃₀₃ are each independentlyselected from a hydrogen, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ aryl group, and a C₁-C₆₀ heteroaryl group);

L₃₀₁ may be the same as explained in connection with L₂₀₁;

R₃₀₁ may be selected from

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazol group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group and a triazinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group;

xb1 may be selected from 0, 1, 2, and 3;

xb2 may be selected from 1, 2, 3, and 4.

wherein in Formula 301,

L₃₀₁ may be selected from

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, and a chrysenylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, and a chrysenylene group, each substitutedwith at least one selected from a deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, anaphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, and a chrysenyl group;

R₃₀₁ may be selected from

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, and a chrysenyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, and a chrysenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, and a chrysenyl group,each substituted with at least one selected from a deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, and a chrysenyl group.

For example, the host may include a compound represented by Formula 301Abelow:

Descriptions of substituents of Formula 301A may be understood byreferring to the descriptions provided herein.

The compound represented by Formula 301 may include at least one ofCompounds H1 to H42.

In some embodiments, the host may include at least one of Compounds H43to H49 below.

An amount of organometallic compound represented by Formula 1 (e.g., asa dopant) in the emission layer may be, e.g., in a range of about 0.01to about 15 parts by weight based on 100 parts by weight of the host.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, e.g., about 200 Å to about 600 Å. When the thickness ofthe emission layer is within this range, excellent light-emissioncharacteristics may be obtained without a substantial increase indriving voltage.

Then, an electron transport region may be disposed on the emissionlayer.

The electron transport region may include at least one selected from ahole blocking layer, an electron transport layer (ETL), and an electroninjection layer.

For example, the electron transport region may have a structure ofelectron transport layer/electron injection layer or a structure of holeblocking layer/electron transport layer/electron injection layer,wherein layers of each structure are sequentially stacked from theemission layer in the stated order.

In an implementation, the organic layer 150 of the organiclight-emitting device may include an electron transport region disposedbetween the emission layer and the second electrode 190, and theelectron transport region may include the organometallic compoundrepresented by Formula 1.

The electron transport region may include a hole blocking layer. Thehole blocking layer may be formed, when the emission layer includes aphosphorescent dopant, to prevent diffusion of excitons or holes into anelectron transport layer.

When the electron transport region includes a hole blocking layer, thehole blocking layer may be formed on the emission layer by using variousmethods, such as vacuum deposition, spin coating casting, a LB method,ink-jet printing, laser-printing, or laser-induced thermal imaging. Whenthe hole blocking layer is formed by vacuum deposition or spin coating,deposition and coating conditions for the hole blocking layer may bedetermined by referring to the deposition and coating conditions for thehole injection layer.

The hole blocking layer may include, for example, at least one of BCPand Bphen.

A thickness of the hole blocking layer may be in a range of about 20 Åto about 1,000 Å, e.g., about 30 Å to about 300 Å. When the thickness ofthe hole blocking layer is within these ranges, the hole blocking layermay have improved hole blocking ability without a substantial increasein driving voltage.

The electron transport region may include an electron transport layer.The electron transport layer may be formed on the emission layer or thehole blocking layer by using various methods, e.g., vacuum deposition,spin coating casting, a LB method, ink-jet printing, laser-printing, orlaser-induced thermal imaging. When an electron transport layer isformed by vacuum deposition or spin coating, deposition and coatingconditions for the electron transport layer may be determined byreferring to the deposition and coating conditions for the holeinjection layer.

According to an embodiment, the organic layer 150 of the organiclight-emitting device may include an electron transport region disposedbetween the emission layer and the second electrode 190. The electrontransport region may include at least one selected from an electrontransport layer and an electron injection layer.

The electron transport layer may further include at least one selectedfrom BCP, Bphen, Alq₃, Balq, TAZ, and NTAZ.

In some embodiments, the electron transport layer may include at leastone compound selected from a compound represented by Formula 601 and acompound represented by Formula 602 illustrated below:Ar₆₀₁-[(L₆₀₁)_(xe1)-E₆₀₁]_(xe2)  <Formula 601>

wherein in Formula 601.

Ar₆₀₁ may be selected from

a naphthalene, a heptalene, a fluorenene, a spiro-fluorene, abenzofluorene, a dibenzofluorene, a phenalene, a phenanthrene, ananthracene, a fluoranthene, a triphenylene, a pyrene, a chrysene, anaphthacene, a picene, a perylene, a pentaphene, and anindenoanthracene;

a naphthalene group, a heptalene group, a fluorenene group, aspiro-fluorenene group, a benzofluorenene group, a dibenzofluorenenegroup, a phenalene group, a phenanthrene group, a anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, and an indenoanthracene group, each substituted withat least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, and—Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃) (wherein Q₃₀₁ to Q₃₀₃ are each independentlyselected from a hydrogen, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ aryl group, and a C₁-C₆₀ heteroaryl group);

L₆₀₁ may be the same as explained in connection with L₂₀₁;

E₆₀₁ may be selected from

a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a furinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group; and

a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group,an imidazopyridinyl group, and an imidazopyrimidinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, C1-C20 alkyl group, C1-C20 alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a pentalenylgroup, an indenyl group, a naphthyl group, an azulenyl group, aheptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenylgroup, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group,an imidazopyridinyl group, and an imidazopyrimidinyl group;

xe1 may be selected from 0, 1, 2, and 3; and

xe2 may be selected from 1, 2, 3, and 4.

wherein in Formula 602,

X₆₁₁ is N or C-(L₆₁₁)_(xe611)-R₆₁₁, X₆₁₂ is N or C-(L₆₁₂)_(xe612)-R₆₁₂,X₆₁₃ is N or C-(L₆₁₃)_(xe613)-R₆₁₃ and, at least one of X₆₁₁ to X₆₁₃ isN;

L₆₁₁ to L₆₁₆ may be the same as explained in connection with L₂₀₁;

R₆₁₁ to R₆₁₆ are each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group; and

xe611 to xe616 may be each independently selected from 0, 1, 2, and 3.

The compound represented by Formula 601 and the compound represented byFormula 602 may be selected from Compounds ET1 to ET15 illustratedbelow.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, e.g., about 150 Å to about 500 Å. When thethickness of the electron transport layer is within the range describedabove, the electron transport layer may have satisfactory electrontransport characteristics without a substantial increase in drivingvoltage.

In an implementation, the electron transport layer may further include,in addition to the materials described above, a metal-containingmaterial.

The metal-containing material may include a Li complex. The Li complexmay include, e.g., Compound ET-D1 (lithium quinolate, LiQ) or ET-D2.

The electron transport region may include an electron injection layerthat allows electrons to be easily provided from the second electrode190.

The electron injection layer may be formed on the electron transportlayer by using various methods, e.g., vacuum deposition, spin coatingcasting, a LB method, ink-jet printing, laser-printing, or laser-inducedthermal imaging. When an electron injection layer is formed by vacuumdeposition or spin coating, deposition and coating conditions for theelectron injection layer may be determined by referring to thedeposition and coating conditions for the hole injection layer.

The electron injection layer may include at least one selected from,LiF, NaCl, CsF, Li₂O, BaO, and LiQ.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, e.g., about 3 Å to about 90 Å. When the thickness ofthe electron injection layer is within the range described above, theelectron injection layer may have satisfactory electron injectioncharacteristics without a substantial increase in driving voltage.

The second electrode 190 is disposed on the organic layer 150 havingsuch a structure. The second electrode 190 may be a cathode that is anelectron injection electrode, and in this regard, a material for formingthe second electrode 190 may be a material having a low work function.Such a material may include a metal, alloy, an electrically conductivecompound, or a mixture thereof. Examples of the material for the secondelectrode 190 may include lithium (Li), magnesium (Mg), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), ormagnesium-silver (Mg—Ag). In some embodiments, the material for formingthe second electrode 190 may be ITO or IZO. The second electrode 190 maybe a reflective electrode, a semi-transmissive electrode, or atransmissive electrode.

Hereinbefore, the organic light-emitting device has been described withreference to FIG. 1.

A C₁-C₆₀ alkyl group used herein refers to a linear or branchedaliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, anddetailed examples thereof are a methyl group, an ethyl group, a propylgroup, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentylgroup, an iso-amyl group, and a hexyl group. A C₁-C₆₀ alkylene groupused herein refers to a divalent group having the same structure as theC₁-C₆₀ alkyl group.

A C₁-C₆₀ alkoxy group used herein refers to a monovalent grouprepresented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group), anddetailed examples thereof are a methoxy group, an ethoxy group, and anisopropyloxy group.

A C₂-C₆₀ alkenyl group used herein refers to a hydrocarbon group formedby substituting at least one carbon double bond in the middle or at theterminal of the C₂-C₆₀ alkyl group, and detailed examples thereof are anethenyl group, a prophenyl group, and a butenyl group. A C₂-C₆₀ alkylenegroup used herein refers to a divalent group having the same structureas the C₂-C₆₀ alkyl group.

A C₂-C₆₀ alkynyl group used herein refers to a hydrocarbon group formedby substituting at least one carbon trip bond in the middle or at theterminal of the C₂-C₆₀ alkyl group, and detailed examples thereof are anethynyl group, and a propynyl group. A C₂-C₆₀ alkylene group used hereinrefers to a divalent group having the same structure as the C₂-C₆₀ alkylgroup.

A C₃-C₁₀ cycloalkyl group used herein refers to a monovalent hydrocarbonmonocyclic group having 3 to 10 carbon atoms, and detailed examplesthereof are a cyclopropyl group, a cyclobutyl group, a cyclopentylgroup, a cyclohexyl group, and a cycloheptyl group. A C₃-C₁₀cycloalkylene group used herein refers to a divalent group having thesame structure as the C₃-C₁₀ cycloalkyl group.

A C₁-C₁₀ heterocycloalkyl group used herein refers to a monovalentmonocyclic group having at least one hetero atom selected from N, O, P,and S as a ring-forming atom and 1 to 10 carbon atoms, and detailedexamples thereof are a tetrahydrofuranyl group, and atetrahydrothiophenyl group. A C₁-C₁₀ heterocycloalkylene group usedherein refers to a divalent group having the same structure as theC₁-C₁₀ heterocycloalkyl group.

A C₃-C₁₀ cycloalkenyl group used herein refers to a monovalentmonocyclic group that has 3 to 10 carbon atoms and at least one doublebond in the ring thereof and does not have aromacity, and detailedexamples thereof are a cyclopentenyl group, a cyclohexenyl group, and acycloheptenyl group. A C₃-C₁₀ cycloalkenylene group used herein refersto a divalent group having the same structure as the C₃-C₁₀ cycloalkenylgroup.

A C₁-C₁₀ heterocycloalkenyl group used herein refers to a monovalentmonocyclic group that has at least one hetero atom selected from N, O,P, and S as a ring-forming atom, 1 to 10 carbon atoms, and at least onedouble bond in its ring. Detailed examples of the C₁-C₁₀heterocycloalkenyl group are a 2,3-hydrofuranyl group and a2,3-hydrothiophenyl group. A C₁-C₁₀ heterocycloalkenylene group usedherein refers to a divalent group having the same structure as theC₁-C₁₀ heterocycloalkenyl group.

A C₆-C₆₀ aryl group used herein refers to a monovalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms, and a C₆-C₆₀arylene group used herein refers to a divalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms. Detailedexamples of the C₆-C₆₀ aryl group are a phenyl group, a naphthyl group,an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and achrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylene groupeach include two or more rings, the rings may be fused to each other.

A C₁-C₆₀ heteroaryl group used herein refers to a monovalent grouphaving a carboncyclic aromatic system that has at least one hetero atomselected from N, O, P, and S as a ring-forming atom, and 1 to 60 carbonatoms. A C₁-C₆₀ heteroarylene group used herein refers to a divalentgroup having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, P, and S as a ring-forming atom, and 1 to 60carbon atoms. Examples of the C₁-C₆₀ heteroaryl group are a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachinclude two or more rings, the rings may be fused to each other.

A C₆-C₆₀ aryloxy group used herein indicates —OA₁₀₂ (wherein A₁₀₂ is theC₆-C₆₀ aryl group), and a C₆-C₆₀ arylthio group used herein indicates—SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

A monovalent non-aromatic condensed polycyclic group used herein refersto a monovalent group (for example, having 8 to 60 carbon atoms) thathas two or more rings condensed to each other, only carbon atoms as aring forming atom, and non-aromacity in the entire molecular structure.A detailed example of the monovalent non-aromatic condensed polycyclicgroup is a fluorenyl group. A divalent non-aromatic condensed polycyclicgroup used herein refers to a divalent group having the same structureas the monovalent non-aromatic condensed polycyclic group.

A monovalent non-aromatic condensed heteropolycyclic group used hereinrefers to a monovalent group (for example, having 2 to 60 carbon atoms)that has two or more rings condensed to each other, has a heteroatomselected from N, O P, and S, other than carbon atoms, as a ring formingatom, and has non-aromacity in the entire molecular structure. Anexample of the monovalent non-aromatic condensed heteropolycyclic groupis a carbazolyl group. A divalent non-aromatic condensedheteropolycyclic group used herein refers to a divalent group having thesame structure as the monovalent non-aromatic condensed heteropolycyclicgroup.

at least one substituent of substituents of the substituted C₃-C₁₀cycloalkylene group, substituted C₁-C₁₀ heterocycloalkylene group,substituted C₃-C₁₀ cycloalkenylene group, substituted C₁-C₁₀heterocycloalkenylene group, substituted C₆-C₆₀ arylene group,substituted C₁-C₆₀ heteroarylene group, substituted divalentnon-aromatic condensed polycyclic group, substituted divalentnon-aromatic condensed heteropolycyclic group, substituted C₁-C₆₀ alkylgroup, substituted C₂-C₆₀ alkenyl group, substituted C₂-C₆₀ alkynylgroup, substituted C₁-C₆₀ alkoxy group, substituted C₃-C₁₀ cycloalkylgroup, substituted C₁-C₁₀ heterocycloalkyl group, substituted C₃-C₁₀cycloalkenyl group, substituted C₁-C₁₀ heterocycloalkenyl group,substituted C₆-C₆₀ aryl group, substituted C₆-C₆₀ aryloxy group,substituted C₆-C₆₀ arylthio group, substituted C₁-C₆₀ heteroaryl group,substituted monovalent non-aromatic condensed polycyclic group, andsubstituted monovalent non-aromatic condensed heteropolycyclic group maybe

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and —C(═O)(Q₁₈);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,or a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidgroup or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —N(Q₂₁)(Q₂₂),—Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and —C(═O)(Q₂₈); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇), and —C(═O)(Q₃₈);

wherein Q₁ to Q₈, Q₁₁ to Q₁₈, Q₂₁ to Q₂₈, and Q₃₁ to Q₃₈ may be eachindependently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arythio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, or a monovalent non-aromaticcondensed heteropolycyclic group.

For example, at least one substituent of substituents of the substitutedC₃-C₁₀ cycloalkylene group, substituted C₁-C₁₀ heterocycloalkylenegroup, substituted C₃-C₁₀ cycloalkenylene group, substituted C₁-C₁₀heterocycloalkenylene group, substituted C₆-C₆₀ arylene group,substituted C₁-C₆₀ heteroarylene group, substituted divalentnon-aromatic condensed polycyclic group, substituted divalentnon-aromatic condensed heteropolycyclic group, substituted C₁-C₆₀ alkylgroup, substituted C₂-C₆₀ alkenyl group, substituted C₂-C₆₀ alkynylgroup, substituted C₁-C₆₀ alkoxy group, substituted C₃-C₁₀ cycloalkylgroup, substituted C₁-C₁₀ heterocycloalkyl group, substituted C₃-C₁₀cycloalkenyl group, substituted C₁-C₁₀ heterocycloalkenyl group,substituted C₆-C₆₀ aryl group, substituted C₆-C₆₀ aryloxy group,substituted C₆-C₆₀ arylthio group, substituted C₁-C₆₀ heteroaryl group,substituted monovalent non-aromatic condensed polycyclic group, andsubstituted monovalent non-aromatic condensed heteropolycyclic group maybe selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a cyclopentylgroup, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a pentalenyl group, an indenylgroup, a naphthyl group, an azulenyl group, a heptalenyl group, anindacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a naphthacenyl group, a picenyl group, a perylenyl group, apentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenylgroup, a coronenyl group, an ovalenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thiadiazolyl group, animidazopyridinyl group, an imidazopyrimidinyl group, —N(Q₁₁)(Q₁₂),—Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and —C(═O)(Q₁₆);

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a pentalenylgroup, an indenyl group, a naphthyl group, an azulenyl group, aheptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenylgroup, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group,an imidazopyridinyl group, and an imidazopyrimidinyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a pentalenylgroup, an indenyl group, a naphthyl group, an azulenyl group, aheptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenylgroup, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group,an imidazopyridinyl group, and an imidazopyrimidinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a pentalenyl group, an indenylgroup, a naphthyl group, an azulenyl group, a heptalenyl group, anindacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a naphthacenyl group, a picenyl group, a perylenyl group, apentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenylgroup, a coronenyl group, an ovalenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thiadiazolyl group, animidazopyridinyl group, an imidazopyrimidinyl group, —N(Q₂₁)(Q₂₂),—Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and —C(═O)(Q₂₆); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇), and —C(═O)(Q₃₆);

wherein Q₁₁ to Q₁₈, Q₂₁ to Q₂₈, and Q₃₁ to Q₃₈ may be each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenylgroup, a pentalenyl group, an indenyl group, a naphthyl group, anazulenyl group, a heptalenyl group, an indacenyl group, an acenaphthylgroup, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a naphthacenyl group, apicenyl group, a perylenyl group, a pentaphenyl group, a hexacenylgroup, a pentacenyl group, a rubicenyl group, a coronenyl group, anovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group,an imidazolyl group, a pyrazolyl group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anisoindolyl group, an indolyl group, an indazolyl group, a purinyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aphthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzoimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thiadiazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group.

Hereinafter, an organic light-emitting device according to an embodimentis described in detail with reference to Synthesis Example and Examples.The wording “B was used instead of A” used in describing SynthesisExamples means that a molar equivalent of A was identical to a molarequivalent of B.

The following Examples and Comparative Examples are provided in order tohighlight characteristics of one or more embodiments, but it will beunderstood that the Examples and Comparative Examples are not to beconstrued as limiting the scope of the embodiments, nor are theComparative Examples to be construed as being outside the scope of theembodiments. Further, it will be understood that the embodiments are notlimited to the particular details described in the Examples andComparative Examples.

EXAMPLE Synthesis Example 1 Synthesis of Compound 1 Synthesis ofIntermediate 1

Intermediate 1 was synthesized according to Reaction Scheme 1-1 below:

6.26 g (17.3 mmol) of3-((1H-benzo[d]imidazole-1-yl)methyl)-9-(1,3,5-triazine-2-yl)-9H-carbazolewas dissolved in 45 mL of 2-ethoxyethanol, and then, 2.4 g (7.6 mmol) ofiridium chloride hydrate (IrCl₃.3H₂O) and 15 mL of distilled water wereadded thereto, and the result was stirred at a temperature of 130° C.for 20 hours. Once the reaction was complete, the reaction solution wascooled to ambient temperature and a precipitate was filtered therefrom.The precipitate was washed with methanol and dried in a vacuum conditionto produce.

Synthesis of Compound 1

Compound 1 was Synthesized According to Reaction Scheme 1-2 Below:

5.37 g (4.56 mmol) of Intermediate 1 obtained through Reaction Scheme1-1, 4.12 g (11.4 mmol) of3-((1H-benzo[d]imidazole-1-yl)methyl)-9-(1,3,5-triazine-2-yl)-9H-carbazole,and 0.5 g of K₂CO₃ were added to 30 mL of 2-ethoxyethanol, and then, themixture was stirred at a temperature of 130° C. for 12 hours. Once thereaction was complete, the reaction solution was cooled to ambienttemperature (25° C.) and a precipitate was filtered therefrom and washedwith methanol. The precipitate was dissolved by using dichloromethaneand then filtered through a silica short pad, and the filtereddichloromethane solution was boiled and methanol was slowly addedthereto to precipitate 3.20 g (yield: 55%) of Compound 1.

¹H-NMR: 8.86 (6H), 8.55 (3H), 8.10 (1H), 7.95 (3H), 7.63 (3H), 7.59(3H), 7.49 (3H) 7.29 (3H) 7.20 (6H)

APCI-MS (m/z): 1278[M+]

Synthesis Example 2 Synthesis of Compound 2 Synthesis of Intermediate 2

6.26 g (17.3 mmol) of3-((1H-benzo[d]imidazole-1-yl)methyl)-9-(1,3,5-triazine-2-yl)-9H-carbazolewas dissolved in 45 mL of 2-ethoxyethanol, and then, 2.4 g(7.6 mmol) ofiridium chloride hydrate (IrCl₃.3H₂O) and 15 mL of distilled water wereadded thereto, and the result was stirred at a temperature of 130° C.for 20 hours. When the reaction was complete, the reaction solution wascooled to ambient temperature. A precipitate was filtered therefrom andwashed with methanol and dried in a vacuum condition to produce 5.37 g(yield: 60%) of Intermediate 2 that is a dimer.

Synthesis of Compound 2

5.37 g (4.56 mmol) of Intermediate 2, 1.76 g (11.4 mmol) of 2-phenylapyridine, and 0.5 g of K₂CO₃ were added to 30 mL, of 2-ethoxyethanol,and then, the result was stirred at a temperature of 130° C. for 12hours. Once the reaction was complete, the reaction solution was cooledto ambient temperature (25° C.) and a precipitate was filtered therefromand washed with methanol. The precipitate was dissolved by usingdichloromethane, and then filtered through a silica short pad, and thefiltered dichloromethane solution was boiled, and methanol was slowlyadded thereto to produce 2.93 g (yield: 60%) of Compound 2.

¹H-NMR: 8.87 (4H), 8.56 (3H), 8.30 (1H), 8.12 (2H), 7.98 (3H), 7.83(2H), 7.63 (2H), 7.59 (2H), 7.54 (2H), 7.51 (2H), 7.22 (6H), 7.00 (2H)

APCI-MS (m/z): 1071 [M+]

Synthesis Example 3 Synthesis of Compound 3 Synthesis of Intermediate 3

6.26 g (17.3 mmol) of3-((1H-benzo[d]imidazole-1-yl)methyl)-9-(1,3,5-triazine-2-yl)-9H-carbazolewas dissolved in 45 mL of 2-ethoxyethanol, and then, 2.4 g(7.6 mmol) ofiridium chloride hydrate (IrCl₃.3H₂O) and 15 mL of distilled water wereadded thereto, and the result was stirred at a temperature of 130° C.for 20 hours. Once the reaction was complete, the reaction solution wascooled to ambient temperature, and a precipitate was filtered therefromand washed by using methanol and dried in a vacuum condition to produce5.37 g(yield: 60%) of Intermediate 3 that is a dimer.

Synthesis of Compound 3

5.37 g (4.56 mmol) of Intermediate 3, 2.17 g (11.4 mmol) of2-(2,4-difluorophenyl)pyridine, and 0.5 g of K₂CO₃ were added to 30 mLof 2-ethoxyethanol, and then, the result was stirred at a temperature of130° C. for 12 hours. Once the reaction was complete, the reactionsolution was cooled to ambient temperature (25° C.) and a precipitatewas filtered therefrom and washed with methanol. The precipitate wasdissolved by using dichloromethane and filtered through a silica shortpad, and the filtered dichloromethane solution was boiled and methanolwas slowly added thereto to produce 2.92 g (yield: 58%) of Compound 3.

¹H-NMR: 8.87 (4H), 8.56 (3H), 8.12 (2H), 7.98 (3H), 7.83 (2H), 7.63(2H), 7.59 (2H), 7.51 (3H), 7.22 (6H), 7.00 (3H)

APCI-MS (m/z): 1105[M+]

Synthesis Example 4 Synthesis of Compound 5 Synthesis of Intermediate 4

6.26 g (17.3 mmol) of3-((1H-benzo[d]imidazole-1-yl)methyl)-9-(1,3,5-triazine-2-yl)-9H-carbazolewas dissolved in 45 mL of 2-ethoxyethanol, and then, 2.4 g(7.6 mmol) ofiridium chloride hydrate (IrCl₃.3H₂O) and 15 mL of distilled water wereadded thereto, and the result was stirred at a temperature of 130° C.for 20 hours. Once the reaction was complete, the reaction solution wascooled to ambient temperature, and a precipitate was filtered therefromand washed by using methanol and dried in a vacuum condition to produce5.37 g(yield: 60%) of Intermediate 4 that is a dimer.

Synthesis of Compound 5

5.37 g (4.56 mmol) of Intermediate 4, 2.54 g (11.4 mmol) of2-(2,4-dicyano-3-fluorophenyl)pyridine, and 0.5 g of K₂CO₃ were added to30 mL of 2-ethoxyethanol, and then, the result was stirred at atemperature of 130° C. for 12 hours. Once the reaction was complete, thereaction solution was cooled to ambient temperature (25° C.) and aprecipitate was filtered therefrom and washed with methanol. Theprecipitate was dissolved by using dichloromethane and then filteredthrough a silica short pad, and the filtered dichloromethane solutionwas boiled and methanol was slowly added thereto to precipitate 2.85 g(yield: 55%) of Compound 5.

¹H-NMR: 8.87 (4H), 8.56 (3H), 8.12 (2H), 8.04 (1H) 7.98 (4H), 7.83 (2H),7.63 (2H), 7.59 (2H), 7.51 (3H), 7.22 (6H), 7.00 (1H)

APCI-MS (m/z): 1136[M+]

Example 1

An ITO glass substrate (a product of Corning Co., Ltd) having a sheetresistance of 15 Ω/cm² and a thickness of 500 Å as an anode was cut to asize of 50 mm×50 mm×0.7 mm, and then, sonicated by using isopropylalcohol and pure water each for 5 minutes, and cleaned by the exposureto ultraviolet rays for 30 minutes, and then ozone, and the ITO glasssubstrate was mounted on a vacuum deposition apparatus.

2-TNATA was vacuum deposited on the ITO glass substrate to form a holeinjection layer having a thickness of 600 Å, and then, NPB was vacuumdeposited on the hole injection layer to form a hole transport layerhaving a thickness of 300 Å. Then, Compound 100 (host) and Compound 1(dopant) were co-deposited at a weight ratio of 95:5 on the holetransport layer layer to form an emission layer having a thickness of300 Å.

Then. Compound ET1 was deposited on the emission layer to form anelectron transport layer having a thickness of 300 Å, and LiF wasdeposited on the electron transport layer to form an electron injectionlayer having a thickness of 10 Å, and Al was deposited on the electroninjection layer to form a cathode having a thickness of 1,000 Å, therebycompleting the manufacture of an organic light-emitting device.

Example 2

An organic light-emitting device was manufactured in the same manner asin Example 1, except that in forming the emission layer, as a dopant,Compound 2 was used instead of Compound 1.

Example 3

An organic light-emitting device was manufactured in the same manner asin Example 1, except that in forming the emission layer, as a dopant,Compound 3 was used instead of Compound 1.

Example 4

An organic light-emitting device was manufactured in the same manner asin Example 1, except that in forming the emission layer, as a dopant,Compound 5 was used instead of Compound 1.

Example 5

An organic light-emitting device was manufactured in the same manner asin Example 1, except that in forming the emission layer, as a dopant,Compound 7 was used instead of Compound 1.

Comparative Example 1

An organic light-emitting device was manufactured in the same manner asin Example 1, except that in forming the emission layer, as a dopant,Compound A was used instead of Compound 1.

Comparative Example 2

An organic light-emitting device was manufactured in the same manner asin Example 1, except that in forming the emission layer, as a dopant,Compound B was used instead of Compound 1.

Evaluation Example 1

The driving voltage and luminescent efficiency (at a current density of10 mA/cm²) of the organic light-emitting devices manufactured accordingto Examples 1-5 and Comparative Examples 1 and 2 were measured by usinga PR650 Spectroscan Source Measurement Unit. (a product of PhotoResearchInc.)

TABLE 1 Emission layer Driving voltage Efficiency Emission dopant (V)(cd/A) color Example 1 Compound 1 4.3 22.9 Blue Example 2 Compound 2 4.521.8 Blue Example 3 Compound 3 4.6 18.3 Blue Example 4 Compound 5 4.417.2 Blue Example 5 Compound 7 4.5 19.6 Blue Comparative Compound A 4.715.4 Blue Example 1 Comparative Compound B 4.8 13.2 Blue Example 2

From Table 1, it may be that the driving voltage and luminescentefficiency of the organic light-emitting devices manufactured accordingto Examples 1 to 5 are higher than the driving voltage and luminescentefficiency of the organic light-emitting devices manufactured accordingto Comparative Examples 1 and 2.

An organic light-emitting device including the organometallic compoundaccording to an embodiment may have a low driving voltage, highefficiency, high brightness, and a long lifespan.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. An organometallic compound represented by thefollowing Formula 1:M(L₁)_(n1)(L₂)_(n2)  <Formula 1> wherein in Formula 1, M is selectedfrom iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium(Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), andrhodium (Rh); n1 is 0, 1, 2, or 4; n2 is 1, 2, or 3; when n1 is two ormore, two or more L₁ are identical or different, and when n2 is two ormore, two or more L₂ are identical or different; L₁ is selected from amonovalent organic ligand, a divalent organic ligand, a trivalentorganic ligand, and a tetravalent organic ligand, and is different fromL₂; L₂ is a ligand represented by the following Formula 2;

wherein in Formula 2, X₁ is N or C(R₁), X₂ is N or C(R₂), X₃ is N orC(R₃), and X₄ is N or C(R₄); X₅ is N, C, or C(R₅), X₆ is N, C, or C(R₆),X₇ is N, C, or C(R₇), X₈ is N, C, or C(R₈), and two of X₅ to X₈ are C,when X₅ is C, X₅ binds to M or N of a benzimidazole-based moiety inFormula 2; when X₆ is C, X₆ binds to M or N of the benzimidazole-basedmoiety in Formula 2; when X₇ is C, X₇ binds to M or N of thebenzimidazole-based moiety in Formula 2; when X₈ is C, X₈ binds to M orN of the benzimidazole-based moiety in Formula 2; X₉ is N or C(R₉), X₁₀is N or C(R₁₀), X₁₁ is N or C(R₁₁), X₁₂ is N or C(R₁₂); R₁ to R₁₂ areeach independently selected from: a hydrogen, —F, a cyano group, a nitrogroup, a methyl group, an ethyl group, a propyl group, an n-butyl group,an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, or a triazinylgroup; a methyl group, an ethyl group, a propyl group, an n-butyl group,an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, or a triazinylgroup, each substituted with at least one selected from —F, a cyanogroup, a nitro group, a phenyl group, a naphthyl group, a pyridinylgroup, a pyrimidinyl group, a triazinyl group, and —Si(Q₃₃)(Q₃₄)(Q₃₅);and —Si(Q₃)(Q₄)(Q₅), wherein Q₃ to Q₅ are each independently selectedfrom a hydrogen, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a pyridinyl group, a pyrimidinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group; R₁₃ andR₁₄ are each independently a hydrogen or a phenyl group; R₁ to R₄ areseparate or two of R₁ to R₄ bind to each other to form a saturated orunsaturated ring, R₉ to R₁₂ are separate or two of R₉ to R₁₂ bind toeach other to form a saturated or unsaturated ring, R₁₃ and R₁₄ areseparate or R₁₃ and R₁₄ bind to each other to form a saturated orunsaturated ring; * and *′ each indicate a binding site to M inFormula
 1. 2. The organometallic compound as claimed in claim 1,wherein: M is iridium (Ir), n1 is 0, 1, or 2, n2 is 1, 2, or 3, and asum of n1 and n2 is 3; or M is platinum (Pt), n1 is 0, 1, or 2, n2 is 1or 2, and a sum of n1 and n2 is
 2. 3. The organometallic compound asclaimed in claim 1, wherein L₂ in Formula 1 is a ligand represented byone of the following Formulae 2A to 2F:

wherein, in Formulae 2A to 2F, R₁ to R₁₄, *, and *′ are defined the sameas R₁ to R₁₄, * and *′ of Formula
 2. 4. The organometallic compound ofclaim 1, wherein L₁ in Formula 1 is a ligand represented by thefollowing Formula 3:

wherein, in Formula 3, Y₁ to Y₄ are each independently carbon (C) ornitrogen (N); Y₁ and Y₂ are linked to each other via a single bond or adouble bond, and Y₃ and Y₄ are linked to each other via a single bond ora double bond; CY₁ and CY₂ are each independently selected from abenzene group, a naphthalene group, a fluorene group, a spiro-fluorenegroup, an indene group, a pyrrol group, a thiophene group, a furangroup, a imidazole group, a pyrazole group, a thiazole group, anisothiazole group, an oxazole group, an isoxazole group, a pyridinegroup, a pyrazine group, a pyrimidine group, a pyridazine group, aquinoline group, an isoquinoline group, a benzoquinoline group, aquinoxaline group, a quinazoline group, a carbazole group, abenzoimidazole group, a benzofuran group, a benzothiophene group, anisobenzothiophene group, a benzoxazole group, an isobenzoxazole group, atriazole group, a tetrazole group, an oxadiazole group, a triazinegroup, a dibenzofuran group, and a dibenzothiophene group; R₂₁ and R₂₂are each independently selected from: a hydrogen, a deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, —SF₅, a C₁-C₂₀ alkyl group, and a c₁-C₂₀ alkoxygroup; a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substitutedwith at least one selected from a denterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a phenyl group, a naphthyl group, a pyridinyl group, and apyrimidinyl group; a phenyl group, a naphthyl group, a fluorenyl group,a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolylgroup, a thiophenyl group, a furanyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, apyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolylgroup, an indazolyl group, a purinyl group, a quinolinyl group, aisoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, and an imidazopyrimidinyl group; and aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthyenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazoly; group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazoly group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, an imidazopyrimidinyl group, and —Si(O₄₁)(O₄₂)(O₄₃), eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group,a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthrolinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, ans an imidazopyrimidinyl group; a1 and a2 are each independently0, 1, 2, or 3; O₄₁ to O₄₃ are each independently selected from ahydrogen, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, anaphtlyl group, a pyridinyl group, a pyrimidinyl group, and a triazinylgroup; and * and *′ each indicate a binding site to M in Formula
 1. 5.The organometallic compound as claimed in claim 4, wherein: CY₁ is abenzene group, a pyridine group, a pyrimidine group, or a triazinegroup, CY₂ is a pyridine group, an imidazole group, a pyrazole group, atriazole group, or a tetrazole group; R₂₁ and R₂₂ are each independentlyselected from: a hydrogen, —F, a cyano group, a nitro group, —SF₅, amethyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a dibenzofuranyl group, and a dibenzothiophenyl group; and amethyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a dibenzofuranyl group and a dibenzothiophenyl group, eachsubstituted with at least one selected from —F, a cyano group and anitro group; and a1 and a2 are each independently 0, 1, 2, or
 3. 6. Theorganometallic compound as claimed in claim 1, wherein L₁ in Formula 1is a ligand represented by one of the following Formulae 3-1 to 3-24:

wherein, in Formulae 3-1 to 3-24, R₂₁ and R₂₂ are each independentlyselected from: a hydrogen, —F, a cyano group, a nitro group, —SF₅, amethyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a dibenzofuranyl group, and a dibenzothiophenyl group; and amethyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a dibenzofuranyl group and a dibenzothiophenyl group, eachsubstituted with at least one selected from —F, a cyano group and anitro group; a11 and a21 are each independently 1, 2, 3, or 4; a12 anda22 are each independently 1, 2, or 3, a13 and a23 are eachindependently 1 or 2; and * and *′ each indicate a binding site to M inFormula
 1. 7. The organometallic compound as claimed in claim 1, whereinL₁ in Formula 1 is a ligand represented by one of the following Formulae4-1 to 4-4:

wherein, in Formulae 4-1 to 4-4, Z_(21b), Z_(21c), Z_(21d), and Z_(22b)are each independently selected from: —F, a cyano group, a nitro group,a methyl group, an ethyl group, a propyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tort-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decanyl group, an isodecanyl group, asec-decanyl group, a tert-decanyl group, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, a pentoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, and atriazinyl group; a methyl group, an ethyl group, a propyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decanyl group, anisodecanyl group, a sec-decanyl group, a tert-decanyl group, a methoxygroup, an ethoxy group, a propoxy group, a butoxy group, a pentoxygroup, a phenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group, each substituted with at leastone selected from —F, a cyano group, a nitro group, a phenyl group, anaphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, and —Si(Q₃₃)(Q₃₄)(Q₃₅); and —Si(Q₃)(Q₄)(Q₅); wherein Q₃ to Q₅ andQ₃₃ to Q₃₅ are each independently selected from a hydrogen, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a triazinyl group, a quinolinylgroup, and an isoquinolinyl group.
 8. The organometallic compound asclaimed in claim 7, wherein Z_(21b), Z_(21c), and Z_(21d) are eachindependently selected from —F, —Cl, —CN and —NO₂; and a C₁-C₂₀ alkylgroup and a C₁-C₂₀ alkoxy group, each substituted with at least oneselected from —F, —Cl, —CN, and —NO₂, and Z_(22b) is selected from aC₁-C₂₀ alkyl group and —N(Q₄₁)(Q₄₂), wherein Q₄₁ and Q₄₂ are eachindependently selected from a hydrogen, a C₁-C₂₀ alkyl group, a phenylgroup, a naphthyl group, and an anthracenyl group.
 9. The organometalliccompound as claimed in claim 1, wherein the organometallic compoundrepresented by Formula 1 is represented by one of the following Formulae1-1 to 1-24:

wherein, in Formulae 1-1 to 1-24, M is iridium (Ir) or platinum (Pt); n1is 0, 1, or 2, n2 is 1, 2, or 3, and a sum of n1 and n2 is 2 or 3; R₁ toR₁₂ are each independently selected from: a hydrogen, —F, a cyano group,a nitro group, a methyl group, an ethyl group, a propyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decanyl group, anisodecanyl group, a sec-decanyl group, a tert-decanyl group, a methoxygroup, an ethoxy group, a propoxy group, a butoxy group, a pentoxygroup, a phenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group; a methyl group, an ethylgroup, a propyl group, an n-butyl group, an isobutyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an isopentyl group, asec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decanyl group, an isodecanyl group, a sec-decanyl group, atert-decanyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, or a triazinyl group, eachsubstituted with at least one selected from —F, a cyano group, a nitrogroup, a phenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, a triazinyl group, and —Si(Q₃₃)(Q₃₄)(Q₃₅); and—Si(Q₃)(Q₄)(Q₅), wherein Q₃ to Q₅ and Q₃₃ to Q₃₅ are each independentlya hydrogen, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinylgroup, a quinolinyl group, or an isoquinolinyl group; R₁₃ and R₁₄ areeach independently selected from a hydrogen or a phenyl group; R_(21b),R_(21c), and R_(21d) are each independently selected from —F, —Cl, —CNand —NO₂; and a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, eachsubstituted with at least one selected from —F, —Cl, —CN, and —NO₂,R_(22b) is selected from a C₁-C₂₀ alkyl group and —N(Q₄₁)(Q₄₂), and Q₄₁and Q₄₂ are each independently selected from a hydrogen, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, and an anthracenyl group. 10.The organometallic compound as claimed in claim 1, wherein theorganometallic compound represented by Formula 1 is one of the followingCompounds 1 to 5, and 7 to 12, 15 to 21, and 23 to 34:


11. An organic light-emitting device, comprising: a first electrode; asecond electrode facing the first electrode; and an organic layerbetween the first electrode and the second electrode, the organic layerincluding an emission layer, wherein the organic layer includes at leastone organometallic compound as claimed in claim
 1. 12. The organiclight-emitting device as claimed in claim 11, wherein the firstelectrode is an anode, the second electrode is a cathode, and theorganic layer includes: a hole transport region between the firstelectrode and the emission layer, the hole transport region including atleast one of a hole injection layer, a hole transport layer, a bufferlayer, and an electron blocking layer, and an electron transport regionbetween the emission layer and the second electrode, the electrontransport region including at least one of a hole blocking layer, anelectron transport layer, and an electron injection layer.
 13. Theorganic light-emitting device as claimed in claim 11, wherein theemission layer includes the at least one organometallic compound. 14.The organic light-emitting device as claimed in claim 13, wherein theemission layer further includes a host.